Food Safety Bulletin Issue No 4 2006

Feature Articles

I) The International Numbering System (INS) for Food Additives

What are food additives?

Food additives are any natural or synthetic chemical substance added to food in its manufacturing or processing which include preservatives, antioxidants, colouring matters and sweeteners. According to the Food and Drugs (Composition and Labelling) Regulations (Cap 132W), food additives do not include vitamins, minerals or other nutrients used for enriching food, or seasoning such as salt, herbs and spices.

Functions of food additives

Different food additives have different functions. Many of them can extend the shelf-life of food with a view to enhancing food safety and minimizing wastage. Some can even improve the organoleptic properties and appearance of food. Consumers can purchase food with stable quality at reasonable prices.

Principles for using food additives

Food manufacturers should observe the following principles when using additives:

  1. The food additives being used should present no harm to consumers and should not mislead consumers.
  2. The use of food additives must achieve the following objectives:
    1. to preserve the nutritional quality of the food;
    2. to enhance the keeping quality or stability of food or to improve its organoleptic properties;
    3. to facilitate the processing, packaging, transport or storage of food
    provided that these objectives cannot be achieved by other economical and feasible means. Besides, food additives should not be used to disguise the denatured raw materials or the effects of undesirable practices during the course of food manufacturing.
  3. All food additives used must comply with the "good manufacturing practice", that is, use food additives only when required and never excessively. Food additives should be treated in the same way as food ingredients to ensure hygiene and food safety.

Regulation on the use of food additives

Food manufactures must ensure that the types and quantity of food additives they intend to use conform to Part V of the Public Health and Municipal Services Ordinance (Cap.132) and its subsidiary legislation (Preservatives in Food Regulations, Colouring Matter in Food Regulations, Sweeteners in Food Regulations, and Food and Drugs (Composition and Labelling) Regulations). The Centre for Food Safety monitors the use of food additives and enforces the relevant legislation.

Why is it necessary to set out information about food additives on food labels?

As some people may have adverse or allergic reactions to certain food additives, it is necessary to enable consumers to avoid unsuitable food by informing them about the food additives used. The Government formulated the Food and Drugs (Composition and Labelling)(Amendment) Regulation 2004 (the Regulation) stipulating that all food additives used and their functional classes must be declared explicitly on the labels of prepackaged food. The Regulation was enacted on 9 July 2004. However, to allow food manufacturers more time to adapt to the new requirements, there was a grace period of 36 months.

What is the International Numbering System (INS)?

The Government appreciates the difficulty of manufacturers in listing the full names of all additives, which are often long and complex, within the limited space of the food label. Therefore, the Regulation allows manufacturers to use the identification numbers under the International Numbering System (INS) for Food Additives, compiled by the Codex Alimentarius Commission (Codex)*, instead of the names of food additives. Furthermore, when specifying a food additive in the food, manufacturers are also at liberty to use the prefix "E" or "e" with the INS number as adopted by the European Union under the E-numbering system.

The use of identification numbers simplifies and standardises the way food additives are labelled. This will help consumers to make informed choices without causing extra burden to the trade.

The INS, compiled by Codex, is used for identifying food additives. However, the INS does not include flavours, chewing gum bases, or dietetic and nutritive additives.

Not all chemicals present in the INS are allowed to be used in food for sale in Hong Kong. Manufacturers have to abide by the regulations prescribed in Part V of the Public Health and Municipal Services Ordinance (Cap.132) and its subsidiary legislation.

Classification of Food Additives

Codex has classified food additives into 23 functional classes according to their usages. Consumers can learn the function of an individual food additive from the class it belongs. The 23 functional classes are listed below:-

  1. Acid
  2. Acidity regulator
  3. Anti-caking agent
  4. Anti-foaming agent
  5. Antioxidant
  6. Bulking agent
  7. Colour
  8. Colour retention agent
  9. Emulsifier
  10. Emulsifying salt
  11. Firming agent
  12. Flavour enhancer
  13. Flour treatment agent
  14. Foaming agent
  15. Gelling agent
  16. Glazing agent
  17. Humectant
  18. Preservative
  19. Propellant
  20. Raising agent
  21. Stabilizer
  22. Sweetener
  23. Thickener

List of Food Additives

For easy reference, the List of Food Additives has three columns, namely "identification numbers", "names of the food additives" and "technical functions". The List is arranged in two orders: (i) numerical order of the identification numbers; and (ii) alphabetical order of the names of the food additives.

Applications of the List of Food Additives and INS

From the identification number(s) shown on a food label, consumers can easily check the food additive(s) used in foods from the List of Food Additives. Here is an example:

According to the List of Food Additives, the identification number 331 stands for sodium citrates. We then know that the food contains sodium citrates and can decide whether we can take the food.

The List of Food Additives is updated regularly. Please visit the websites of the Food and Environmental Hygiene Department ( or the Codex ( for the updated list and relevant information.

* The Codex Alimentarius Commission, an international body formed by the Food and Agriculture Organization and the World Health Organization of the United Nations in 1963, is responsible for developing food related standards. China officially joined Codex in 1986.

(II) Public Consultation on Proposed Amendment to the Preservatives in Food Regulations

To enhance food safety for the protection of public health and consumer interest, the Government regularly reviews the local food legislation to keep it abreast with the latest international development.

In the light of rapid advancement in food science and technology, the Government considers it necessary to revise the existing Preservatives in Food Regulations to bring them in line with the standards adopted by Codex. The proposed amendments include incorporation of Codex's standards for preservatives and antioxidants into the existing Regulations and introduction of a food category system.

Public consultation on the proposed amendments will be conducted. Please check the webpage of the Centre for Food Safety ( for details.

(III) Expert Committee on Food Safety

To further strengthen the consultative framework on food safety, Dr. York Chow, the Secretary for Health, Welfare and Food, appointed in September 2006 more than 10 members to the Expert Committee on Food Safety (the Committee) of the Centre for Food Safety (CFS). These members include academics and professionals from Hong Kong, the Mainland and overseas, as well as trade and consumer representatives. They will serve a term of two years with effect from 15 September 2006.

The Committee is to advise the Director of Food and Environmental Hygiene on food safety operational strategies and measures to protect public health, standards and guidelines relating to food safety and food composition and their application in Hong Kong. Moreover, the Committee also advises on the implementation of food safety risk communication and public education programmes as well as new directions for research to be commissioned by the CFS. The Committee held its first meeting in October 2006.

The Committee is chaired by Professor Kwan Hoi-shan, Dean of the Faculty of Science and Professor of Biology of the Chinese University of Hong Kong. He is a well-established academic in food and nutritional science specialising in food science, food microbiology and molecular biotechnology. Members include Mainland and overseas experts. They are Dr. Kan Xue-gui from the Bureau of Health Supervision of the Ministry of Health of the People's Republic of China, Dr. Chua Sin-bin, Director-General and Chief Veterinary Officer of the Agri-Food and Veterinary Authority of Singapore and Dr. Marion Joy Healy, Chief Scientist of the Food Standards Australia New Zealand (FSANZ). Local members appointed include Dr. Chan Pui-kwong, Professor Thomas Chan Yan-keung, Mr. Colin KC Cheng, Mrs. Jenny Fung Ma Kit-han, Mr. Peter Johnston, Ms. Connie Lau Yin-hing, Dr. Lau Fei-lung, Dr. Frederick Leung Chi-ching, Dr. Lo King-shun, Dr. Desmond K O'Toole, Professor Jonathan Wong Woon-chung, Dr Raymond Wong Sze-chung, Mr. Simon Wong Ka-wo and Dr. Carrie Willis, Representatives of the Agriculture, Fisheries and Conservation Department and representatives of the Department of Health.

(IV) Don't Forget Food Safety when Celebrating Christmas

Christmas is approaching and many people will spend the festive time with their friends and relatives at home. We should be aware of the potential risk in preparing the Christmas banquet to ensure food safety.

Party food involves great varieties of food ingredients and many preparation procedures. The average household may not have enough stoves, refrigerators and food warming devices to prepare a lot of food. Early preparation also increases the risk of contamination. Besides, food brought by guests may have been kept at room temperature for some time, resulting in mass bacterial growth. When planning a Christmas party, observe the following guidelines to ensure the food is safe and wholesome:

Tips for Food Preparation

Tips for Food Consumption

Tips for Keeping the Remaining Food

Food Safety Tips

Smart Tips to Differentiate Various Types of Preserved Fruits

Many people like to snack on preserved fruits such as preserved plums, preserved grapefruits or dried mangoes at home or when they go out. With regard to the recent coverage on the use of preservatives in preserved fruits, let's take a look at relevant stipulations in the Preservatives in Food Regulations (Cap 132BD). Preserved fruits are classified according to their processing methods. The most common types are "crystallized fruits", "glace fruits", "drained fruits", "dried fruits" and "pickles". For glace food, the shelf-life is extended by using syrup which will effect osmosis. For dried food, deterioration is retarded by dehydration under high temperature and low humidity.

Preservatives are common food additives used for inhibiting or retarding the process of deterioration of food. The types and statutory limits of preservatives permitted for use vary according to the physical properties of the food such as its composition, pH value, water content, etc as well as the process and ingredients involved in manufacturing. For example, "dried mangoes" fall within the specified food under Item 31 or 32 of Part 1, Schedule 1 of the Preservatives in Food Regulations, its maximum level of preservatives shall be as follows:

Item Specified food Permitted preservative Parts per million not exceeding
31 Fruit, crystallized, glace or drained Sulphur dioxide
benzoic acid
methyl para-hydroxybenzoate
ethyl para-hydroxybenzoate
propyl para-hydroxybenzoate sorbic acid
32 Fruit, dried other than prunes or figs Sulphur dioxide 2000

Advice to Consumers

If the food manufacturers practise "Good Manufacturing Practice" by using the appropriate amount of permitted preservatives prescribed by law, consumption of preserved fruits should have no adverse health effect. Nevertheless, members of the public shall take note of the followings:

Readers' Corner

Are there "Fake Eggs" in the Local Market?

There were media reports about "fake eggs" being sold in the Mainland. Are there "fake eggs" in the local market?

The Food and Environmental Hygiene Department received complaints about "artificial eggs" during the period from 2004 to June 2006. Investigations were conducted and different egg samples were collected for testing which included testing of protein in the egg white, verification of the egg shell and membrane, etc. Results did not show any abnormalities.

Under the laws of Hong Kong, if any person sells to the prejudice of a purchaser any food which is not of the nature, or not of the substance, or not of the quality, of the food demanded by the purchaser, he shall be guilty of an offence. To safeguard food hygiene and safety, FEHD has a food surveillance programme in place for conducting regular sampling tests on food at the import, wholesale and retail levels.

As smart consumers, the public should patronise reputable shops. If in doubt, do not buy the food and call the FEHD hotline on 2868 0000 for complaints.

Activity Highlights

(I) Food Safety Focus

Food Safety Focus, first launched in August 2006, is a bilingual monthly electronic newsletter which provides a new channel of communication between the Centre for Food Centre (CFS) and the general public. It aims to analyse the latest local and overseas food incidents in an in-depth and easy-to-understand manner to enable members of the public to have a better understanding of food hazards, the appropriate measures to reduce the risks and preparedness and response of the Government in handling them. This monthly newsletter is available on the webpage of the CFS ( on the third Wednesday of each month. Columns include "Incident in Focus", "Food Safety Platform", "Food Incident Highlight" and "Summary of Risk Communication Work".

(II) Consumer Liaison Group

Food safety can only be assured through tripartite collaboration between the Government, the trade and consumers. In view of this, a Consumer Liaison Group (CLG) under the Centre for Food Safety (CFS) was officially set up in August 2006 to further improve the communication between the Government and the general public on various food safety issues. The CLG aims to provide a standing platform for FEHD to meet face-to-face with members of the public. FEHD can collect their views on various food safety issues, learn more about their knowledge, attitude and risk perception as regards food safety, thereby tailoring the risk communication messages to cater for their needs.

Members of CLG are invited to attend different focus group meetings according to the topics they are interested in. The first meeting on acrylamide in food was held in September 2006. Members will receive the latest electronic information, including "Risk in Brief", "Risk Assessment Studies", "Food Safety Focus", "Food Alerts" and "Press Release" issued by the CFS.

(III) Photographs and Sidelights of the Food Safety Day – "Prevention of Cross-contamination 食得安心新「煮」意開心嘉年華"

Food Safety Day — "Prevention of cross-contamination" —— was organised by the Centre for Food Safety (CFS) during the summer times at Plaza Hollywood, Diamond Hill. Here are some photos taken at the event for you to enjoy.

To promote "prevention of cross-contamination" the CFS produced jointly with Commercial Radio 1 a food safety radio programme called "The King of Cookery in Food Business." The 10-episode programme has been uploaded to the webpage of the Food and Environmental Hygiene Department ( for the public. Meanwhile, a computer game called "The Smart Chef", which made its debut on Food Safety Day, has also been uploaded to the FEHD's webpage ( Enjoy the game and learn more about food safety.

(IV) International Symposium on Food Safety

The Centre for Food Safety will host an International Symposium on Food Safety with the theme of "Food Safety in the New Era" on 12 and 13 January (Friday and Saturday) 2007 from 9 am to 5 pm at Kowloon Shangri-La. A number of guests and speakers from the Mainland, overseas and local food authorities/institutions are invited to share their experience, foster partnership and promote collaboration in food safety management and control.

The topics of the Symposium will focus on the three aspects of risk analysis in food safety control, namely risk assessment, risk management and risk communication.

The Symposium's target audience are food safety experts, government officials responsible for food safety control and policy makers, members from relevant advisory bodies and committees, the food trade and students.